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A180135 Smallest k such that k*11^n is a sum of two successive primes. 9
5, 18, 6, 24, 6, 32, 40, 26, 20, 94, 50, 26, 10, 168, 30, 18, 196, 126, 70, 166, 30, 54, 130, 26, 50, 10, 40, 28, 20, 120, 84, 26, 228, 336, 92, 174, 24, 308, 28, 102, 216, 232, 68, 112, 192, 252, 512, 302, 110, 10, 330, 30, 138, 150, 168, 770, 70, 264, 24, 72, 180, 198 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

If a(n) == 0 (mod 11), then a(n+1) = a(n)/11.

Records: 5, 18, 24, 32, 40, 94, 168, 196, 228, 336, 512, 770, 996, 1446, 1644, 1812, 1900, 3840, ..., .

Corresponding primes which are twin primes for n = 0, 3, ..., .

LINKS

Robert G. Wilson v, Table of n, a(n) for n = 0..200

MATHEMATICA

f[n_] := Block[{k = 1, j = 11^n/2}, While[ h = k*j; PrimeQ@h || NextPrime[h, -1] + NextPrime@h != 2 h, k++ ]; k]; Array[f, 80, 0]

CROSSREFS

Cf. A180130, A180131, A180132, A180133, A180134, A179975, A180136, A180137, A180138.

Sequence in context: A116911 A097491 A120087 * A260080 A178365 A022142

Adjacent sequences:  A180132 A180133 A180134 * A180136 A180137 A180138

KEYWORD

base,nonn

AUTHOR

Zak Seidov & Robert G. Wilson v, Aug 15 2010

STATUS

approved

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Last modified August 26 00:35 EDT 2019. Contains 326324 sequences. (Running on oeis4.)